Train control



Dec. 27, 1927. 1,654,116

0. H. DIGKE TRAIN CONTROL Filed July 5. 1.924

0 all till Patented Dec. 27, 192?.

UNITED STATES PATENT OFFICE.

ocean a. mean, or nocnnsmnn; NEW YORK, nssxenen TO ennnnnn RAILWAY SIGNAL COMPANY, OF nocnnscrnn, new YORK.

TRAIN CONTROL.

Application filed July 5,

This invention relates to automatic train control systenm of the intermittentinductive type, and more particularly to reliable means for transutiitting control. influences inductively under danger tral'lic conditions ahead regardless of the speed. of the train.

in transmitting control influences inductively from the traclmay to a vehicle at selected control points along the track it has been found that current can be induced. in a car-carried coil when cooperating with a trackway device as a result o'l. uni-directional inagneto motive-tome in either the car-carried or the traclrway device. If this method is used for transu'iitting control influences from the trackway to the vehicle, the speed of the vehicle becon'ies a factor of the value or strength of such control in fineness; in other words, the potential i11- duced in such coil increases with the speed. Since, however, the time during which a car-carried electro-responsive device may respond to such influence also dependent on the speed, that is, decreases as the speed increases, a stronger influence is necessary or at least desirable at high speeds than at lower speeds, and "for this reason it is desirable to transmit control influences at control points by a method in which the strength ot' such influence varies directly with the speed.

in applying automatic train control apparatus to railways it is found expedient to transmit a danger influence at the entrance to a caution block, or say, braking distance in the rear of the exit end of such block corr spoiuling to the entrance to danger territory, and to equip the car-carried apparatus with a suitable delayed action device so that danger traillie conditions are not :liully set up until the train has reached the exit end of such caution block. One well known type of delayed action device is one that is initiated braking distance in the rca r of a danger block, and which gradually sets up more restrictive permissive speed. limits so that a minimum speed. limit oit'. say, 15 miles per hour is set up at the end ot such block. .llia, delayed action dcvircot this type is used it highly important that the influence couinumicating moans tor initiating such device should be 'clicctivc at all speeds, that is, vcr y low speeds as well as higher speeds, so that it assured that the train is properly restricted hen hamburg the exit end i of a caution ried coil in response is induced therein, and to pro 1924. Serial No. 724,334,

block regardless of what its been at the entrance fluence conununicating heretofore mentioned depend to a certain extent on the speed of the vehicle, and have been Found to be ideal for transmitting control influences at average and high train speeds, but have been found inadequate for tran hitting control influences at very low spec Vi ith the above and other considerations inrnind it is proposed in accordance with the pron-lent invention to provide an infln once coin]mniicating means in which the transmission of a control influence depends upon the induction. oft voltage in a car-carto movement of such coil by a field of .tlux due to iu1i-directional mag-neto-inotive-torce'tor initiating a speed restricting device, and to provide additional means which assures initiation of this speed restricting device, whether of the delayed type or whether one that immediately becomes CllihCtlVL, which is made active when the train speed is reduced below a certain predetern'iined low speed, below which the first mentioned influence connnunicating speed may have to such. block. In.-

Ineans ot' the type means cannot be relied upon for transmittinga control influence, which speed may be taken at say, 3 miles per hour. specifically it is proposed to provide a car- :arried core having a, uiii-directional magneto-1uotive-torce induced therein and having a secondary or influence receiving coil associated therewith connected in: series with a stick electro-res1.)ousive device which is adapted to drop such stick eloctro-responsivc device if a voltage of a predetermined value de an armature, preferably of the tractive soft iron type, which it actuated is adapted to de energize suchstick device, provided such armature is actuated when the speed of the train is than the predetermined value of 3 miles per hour hereto'lhrc assumed; and

to equip the traclnvay with suitable clenienls each of which comprises a non-magnetized corc oli magnetic material when in its active coiulition and has a coil thereon closed in a circuit of low resistance when in its inactive condition.

Other objects, purposes and cliarzu-teristic features of the present invention will in part h pointed out hereinafter and in. part be fihvi ue from the ctlrawings More till) 'tem embodying the present that many additional features such as, cab

signals, provision for operating either pilot or tender first, and other various features which are supplemental rather than basic in a train control system may be added.

Referring to the drawings, the reference character 1 des gnates track rails divided by insulating joints 2 into blocks, the block I and the adjacent ends of two other blocks H and J being shown. Since the various blocks are assumed to be equipped the same, like parts of each block are designated by like reference characters having distinctive exponents. Althouglr the train control sys invention may be used without wayside signals, especially if cab signals are used, or may be used with any one of the various types of wayside signals employed in practice, semaphore signals Z only have been shown, and these have been shown conventionally without illustrating'their well known operating devices and control circuits. At the exit end of the block I, the direction of traffic being as indicated by the arrow, is provided a suitable source of trackway energy conventionally illustrated by the battery 3 connected in series with the usual adjustable limiting resistance 4, the entrance end of this block having bridged across the track rails thereof a track relay 5, this track relay,

right hand side thereof, when facing in connection withthe rails 1 of this block and the trackway source of energy, comprising the usual'closed track circuit.

At the entrance end of the block I on the the normal direction of traffic, is shown a knock-down or danger control track element T, comprising a U-shaped core 6, preferably constructed of a high grade of laminated magnetic material and terminating in enlarged pole pleces 7.

V This core 6 is preferably located. so that the top of the poles? are a few inches above the top of the track rails and is provided with a coil 8, which coil under normal clear traffic condi tions ahead is closed in a circuit of low resistance by the front contact 9 of the line or distant relay D; This distant relay D is energized if the block I and the next block in advance thereof are clear, by a circuit ineluding front contact 10 of the track relay 5 and front contact llof the track relay 5).

At the exit end of the block I. and on the left hand side of the trackway are provided two trackway devices R1 and 1th similar to the knock-down track element 'l. These trackway levices RS and RP have their coils 14 and 15 connected in series through a front contact 16 of the track relay 5 under clear traffic conditions ahead, and are adapted to transmit a resetting impulse by the, so-called, transformer reset scheme, when the block ahead is unoccupied, By looking at the drawings it will be noted that the track elements T are active when either the block at the entrance to which they are placed. or the next block in advance thereof, are occupied, by opening of the contact 9, and that the reset elements RS and RP are active, that is, connected in a closed circuit, providing the block in advance thereof is unoccupied; also, that the knock-down element T is active when its control circuit is opened, thus being on the closed circuit princ ple, and that the reset elements RS and RP are active when their circuit is closed. thus being controlled on the open circuit principle. This is, of course, desirable so that a false opening of the c rcuit controlling the track element T changes it to its active condition and a false opening of the circuit controlling the reset device places it in its inactive condition, thus causing both the knock-down and the reset apparatus to function on the side of safety.

On the railway vehicle, which has been conventionally shown by wheels and axles 18 and 19, are provided an influence receiving knock-down car element l1, located on the right hand side thereof, and a pair of reset elements KP and KS, form'ng parts of lhe transformer reset scheme heretofore men tioned. The car element L comprises an inverted U-shaped core 20, terminating in enlarged pole pieces 21 which are located a distance above the track. so as to cooperate with the core (3 of the track element 'l through an air gap of, say. 1 to 2% inches. This core 20 has an air gap therein in which is contained an armature 22 preferably of the tractive soft iron type having a contact 23 connected thereto but insulated therefrom. as shown. This armature 2:! is preferably constructed so as not to increase the reluctance of the core 20 appreciably and also so as not to respond to jars and vibrations of the element l. The reset car elements KP and KS each comprise inverted U- shaped cores 2i and 25 having coils 26 and 27 respectively contained thereon. the coils 26 and 27 respectively being connected in series so that the turns of these coils linlc the core in the same direction.

On the car are provided a control relay CR and a reset relay RS which have for fill llii

imam

a re pond to jars and vibrations to which they are necessarily subjected in practice. These relays are adapted to control a '[DQNIHSSIVQ speed device ofthe delayed act-ion type, and.

for convenience only one type of delayed tLC-- H) tion device has been shown, namely, one of in rice one of the type shown in the the type which is delayed in accordance with the progress of a vehicle along the track. Since the present invention does not relate to any specific form of delayed action deapplication of lVinthrop K. Howe, Ser. No. 38,182 filed July 6, 1915, has been illustrated and will be very-briefly described.

This delayed or retarded cain mechanism includesa centrifugal device C comprising a shaft driven from the axle 18 or 19 in any suitable manner and having}; a grooved collar 3]. slidably contained thereon, which is adapted to be moved up and. down in response to the speed of the vehicleby reason vice G is suitably of centrifugal force acting on the fly balls 32 through links 33 and against the tension of the compression spring 3st contained on this shaft 30. Adjacent the centrifugal demounted a speed. shaft 35having a cam 36 and an angle lever 37 fixedly secured thereto. The angle lever 37 has one of its legsbifurcated andxengaging the groove of the collar 31 and has pivotally secured to the extreme and of the other arm till a floating lever 38 by a pin 39. The free end of this floating lever 38 is bifurcated and contains a roller 40 hearingagainst the earn surface of a cam 41 pinned to the cam shaft dzlrotatably supported in any suitable manner. This coin shaft l2 is biased. to its norinal position by a spring 43 connected to the free end of an arm 4-4 fastened to and projecting from this shaft 42. l

i It will be noted that any intermediate point of the floating lever 38 responds in its [movement to both the position of the cam 41 and the speed of the train as manifested by the speed responsive device (1, and all that is necessary to determine when the speed of the train is excessive for various positions of the cam 41 is to actuate suitable means connected to an intermediate pointof this floating lever 38, Tn thepartienlar arrangenient shown, a link 49 has one end pivotally secured to an interniiediate point of the float inn lever 38, and has its other end pivotally tzonnectedto an eccentrically located pin on a sector 54 journaled on a pin This sector 54 is biased in a COUIItGI ClOClG wise direction by -a spring 70 which in turn urges the roller 40 againstthe 0211141. The sector 54: is shaped to form a cam a depressed or cutaway portion against Whlbllh rollcr72 connected to a spring finger sui table manner under the en gineefis and the L as "l'ollon the control relay (It noel-nixed sullicie having 73 is adapted to ride, so that if this sector tion, the contact 73 separates from the coutact 74:, so that a suitable circuit may be t s o interrupted when the speed oi. the train is excessive.

On the .ttll'hSllttft 423 is also securedv a worm wheel. 4:5 having a nnitilated portion at. This mutilated gear is adaptedto be rotated in one direction or the other, depend.- inp; on the direction of the movement of the vehicle, by a. norm 4;? pinned to a shaft 48 driven from the wheels of the vehicle in any prodetermi ned condi tions of the aiiiparatus. Under normal. clear trailic conditions of the car-carried apparatus this worin 47 is held out of meshed. relation with the worm Wheel 45 by the cam starter nia n'net CS, which has a core pivotally secured to a block 51 in which the shalt 4:8 join'naled. This bloc]: 5]. is biased downwardly by a spring 52 having its other end secured toa lug 5-3, so that if the cam 'arter magnet- CS is (lo-energized, the spring; 52, together with gravity acting on these devices, causes the worm 47 to enpage the worm wheel ah"), the shaft 4:8 being prcfrahly driven through a ijmiversal con ncction from the wheels of the vehicle so that it may be freely moved up and. down by the cam starter n'iagnet CS.

Since the present invention does not re late to any particular type of brake setting device, an eiectro-pneu1nat1c valve EPV has applying device which vents the brake pipe and cuts oil" main reservoir nessure from brake valve when actuated so that he may notrecharn'e the brake pipe, or may control some other type of brake applying device. i

Under normal. condii ions of the apparatus. corrcspoin'lino to clear traiiir ahead the control relay -ll a stick circuit inrludinp; its

secondary coil F; of

is energized by front contact (30 the car element he rinnin sr at the battery Iitl, wire 57 winding of thecontrol relay lt wires 31h and front contact (it) of the con trol relay -R, wires til (3%.! and ('53. contact 223 of thenarelelnent la wires (i i; and (uh second.- ur v coil Fa of the ear olonnintl'i.wirolio hurl; to the ljmtlory lid. The battery till maintains it'ly to just maintain it up under normal conditions andv withoutapprimialtily magnetizing! the core of the (nir eleinent It should die noted that the contact. I of thecar element conditimis till i lit] contact traced as follows:

be noted that the pair encountered first as the train is just about to enter a block, after which the single knock- :I) at the entrance to the block L included in this circuit is shunted by a partial circuit comprising, wire 67, speed contact 68 and wire 69. The speed contact ()8 has a roller 75 pivotally fastened thereto which engages the speed cam 36, so that this contact is opened when and so long as the speed of the train is less than, say, 3 miles per hour.

The primary coil I of the car element L is the flux producing coil. for this element L, and since the presence of flux o'l' a predetermined amount is an essential requisite to the reliable functioning of this car element this primary coil P is energized by a circuit including the brahe applying device EPV', so that interruptionot this circuit or depreciation of current flowing in this circuit below a certain value causesdropping ot the device EPV and eli'ects an automatic application of thebraliesi This circuit may be beginning at the terminal B of a suitable source of direct current such as a battery, wire 78, winding of the EPV, wire 79, cam governor contacts 74 and T3, wire 80, primary coil. P, wire 81 back to a common return wire C connected to the other terminal of such battery. lVith the control relay CR energized the cam starter magnet CS is energized through a circuit including the front 82 ot' the control relay CR, which circuit may readily be traced in the drawings.

' Operatz'omABy looking atthe car-carried influence receiving elements and the track- 'Way influence transmitting elements, itwill ot reset elements is down or. danger control elements comes into communicating relationship. This arrangement is employed, so that when a train is passing through a caution block and it again enters an unoccupied caution block the delayed action device may be restored and again initiated, thereby allowing the train to proceed the same as though it were entering a caution block for the first time, that is, a caution block following a clear block.

'Let' us assume that a train is moving through the block H in the direction of the arrow when the block J in advance thereot is occupied by another train. Under this con dition the track relay 5 is in its (lo-energized position and has its front contact 11 in the lower position so as to de-energize the relay 1, which in turn puts the coil 8 of the track element T in an open circuit and makes this element active. Let us assume that the train is just about to enter a caution block I and passes by the track element T at a speed above 3 miles per hour, that is, with the contact (38 closed. As the car element L passes over the track element T a, rapid increase of flux through the secondary coil S takes place; this is prii'narily due to the decrease of reluctance oi" the magnetic circuit including the OlQll'lOlltS L and T and is to a certain extent, it is believed, due to a diversion of: flux from leakage paths surri'miuling the primary coil P, and to a certain extent to the increase of the total flllX passing through this primary coil P.

This rapid increase of flux in the secondary coils S induces a voltage in the circuit including the control relay CR and the battery 56 which by reason of the manner in which the coils are connected is in a direc tion to oppose the voltage of the battery at) and is ot a value sufficient to decnergize the control relay CR. \Vith the control relay (TR once in its de-energized position and its front contact. (30 opened, thereby interrupting its stick circuit, the relay GR is permanently (lo-energized. As the train proceeds and the car element L recedes from the track element T, and this ncreased flux again decreases to its normal value. a voltage is mduced in the opposite direction in this coil. which voltage is of no avail since the stick circuit has been interrupted. Dropping of the control relay CR causes de-encrgization ot the cam starter magnet CS, thus causing the worm 4:7 to engage worm wheel 44' and in turn causing gradual rotation of the cam 4L1, thereby setting up more restrictive speed limits as the train proceeds through the block. It is of course understood that, if the speed of the train is above the pcrmissive speed limit set up by the cam 41, the angle lever 37, floating lever 38, link 4-9 and sector 54 co-operate to interrupt the energizing circuit for the device EPV. As the train reaches the end ot'the block I, this -am 41 will have assumed its ultimate position and restricted the speed to that desired to be enforced in an occupied block, which for (onvenience may be assumed to be 15 miles per hour.

Let us now assume that the train is moving in the block I with its cam initiated as just explained, but that said another train formerly occupying the block I has passed out of this block. As the train in question is just about to enter the block I and a short distance before the car element L registers with the track element '1. the car-carried resetelements KS and KP register with the reset track devices RP and RS. As heretofore mentioned, this reset arrangement is conveniently called the transformer scheme, this term is preferably used because the car element KP in combination with the tack element RS may be said to comprise one transtormer, and the track element RP in combination with the car-carried element KS may be said to comprise another transformer in which the letters 1 and designate primary and secondary coils of llll lit)

ill

"' trol relay Cit such transl ormers respectively. In any event, it the reset car element KP passes by the track element RS When the contact 16 is closed, which is true \vhenthe block J clear as he; been. assumed, a current indueeal in the seconilary winding l -lby reason ol this; produced by the car element Kl which has its coils 27 eoiuiected to asuitable source of direct current as indicated by the letters l5 and G. Th s current induced in the winding; let of the track element RS caus a rapid building up o'l flux in the track element ill and this rapid increase of tho; in the track element RP, and the rapid change of llui; by reason of registration of the ca r elenient his: therewith and specially due to decrease oi the reluctance oi the min; netic circuit including the eleu'ients HP liifil and the movement oi. the element Kb by the track element lllf, induces ayoltaqc in the coils 26 of theear elen'ient KS, which in turn causes a current to llow in the reset relay Bio thereby closing its trout contact 153 and closing a picl: up circuit for the couwhich is the same as its stick circuit except that its trout contact 60 is shunted by the contact 82% off the reset reiay llhl. l l ith this control. relay Client-e picked up,it will. remain energized l its StiClLtllfeuit iiniludinp the battery 56, so that dropping oi? the reset relay lid, which occurs as soon as the reset devices are out of registration will not :il'lei-t this relay Cl its thus far described it is understood that the cam starter magnet CS is de-ei'ierogized eat-lrt ine that a train enters a caution iii? tlai'iger block and is again re-energized when it. approaches either a caution or a clear hloclr, so that, it throuuh a caut on block and again enters a caut on block, the cam starter magnet GS is inon'iei'itaiily energized and again de-ener- ,llj'lttl upon entering such caution block, so that the cam is reset and may again run down in such caution block; also, that if a train paw-es through a caution block and then enteia-i a danger block, the cam Will i i:.iin in its ultimate run down position and thereafter enforce the miniinun'i speed l mit oil tinned.

Let us now assume that the train pass- 'lh miles per hour hereto'l ore menino; from one clear block into another clear block under which conditions the track ele,- nient T and also the pair ot reset track elellltllll'l ltl? and RS are in. their normal closed circuit condition. As the train passes loyal reset point so that the elements KS and KP reset relay S is inoi'iiientarily picked up without producing; any material effect upon the car-curried apparatus, because the con-- trol relay OR is already energized, Asthe car element L passes by the track element T under the assuiiued condition, insufficient and l a train has passed .irister with track elements RP and RS the voltage is induced in the secondary coil S to drop the controlrelay CR, regardless of the speedot the: train; this,it. believed, is due to the fact that the coil Set the track ele ment '1 acts as a bucking coil, so to speak, and allows insutl'ieieut tlux to pass through thecoro (.5 of this trackelement to materially effect the distribution o'l magnetic llux about tho car element L. In other words, as the cal-element L gets into registration with the track element all. a. very small amount of flux passing through this track element T sets up aqlarge current. in the coil 8, which current flows inpadireetion to oppose a further in creaseuol. flux, so that eventually a rather small amount of flux actually passes through the track element T, thus etlecting a similar increase of flux through the secondary coil S, of, the car element this hange of flux, however, being insufficient to drop the cow trolrela-v- CR. Net, under clear traffic conditions the. track element T produces no e1? feet on the car-carried apparatus as tar as, its action upon the control relay OR is concerned. i

As heretofore mentioned, the induction or potential in a car-carried coilby reason of a clumge of flux due to a constant magnetomotive force and movementof the Vehicle is not suitable to transmit control influences at extren'iely low speeds. To explain, let us assume that the primary coil P of the car elementL is energized to a degree to produce a n1agneto-n1otive-force which is just a trifle than that which is capable of drop ping the control relay CR When the ear passes a track element T in its inactive or shortocircuited condition when the train is moving at the speed at which the influence communicating means functions the best, which in practice has beenfound to be some Where between and miles per hour. lVitli the prin'iary coil P energized to this ex tent insulticient potential is induced in the secondary eoilS ofthe car element L when the car passe. a track element '1. having its coil open cireuited, that is an active element, at speeis less than say, 2 to 3 miles per hour. In other words, the speed range through which the influence communicating means may efliectively be made active or inactive respectively, depending, on whether its coil is open or closed circuited, may extend only from say 2 .n'ii'les per hour upwards. lVhen the speed of the train below a value at which the secondary coil S cannot be relied on to transmit the control influence Which speed may he assumed to he 3 miles per hour, the speed 01111136 assumes a positionso that the roller rides onto the peak of this on a136, thereby opening-the contact 68 and keeping it open so long as the speed rein a ns below this low value, so that the contact 2;} is no longer shunted and it opened drops the relay CR. As the car elen'ient L passes ill) over the track element T having its coil opencircuited, or even if it stands over such element, the magnetic circuit for'the tractive armature 22 and including the trackway core 6 has such little reluctance that enough magnetism passes through the armature 22 so as to attract the same, whereby the contact 23 is opened and the control relay GR is de-energized; so that the control relay GR is deenergized when a train enters a caution block regardless of the speed of the train at the time of registration of elements L and T. It may be stated at this time that the control relay CR also is de-energized when the train enters a clear block at an extremely low speed, because the bucking coil 8 at such speed or certain'l at stand still is unable to buck back the ux so that armature 22 is operated. Although this may at times unnecessarily de-energizethe control relay CR, the engineer in practice is not required to go by a control point at less than 3 miles per hour, and if he does this unnecessarily, he may" be justifiably penalized. Such penalty will induce him to thereafter avoid reducing his speed below-this value when passing atrack element T under clear traffic conditions.

A train control system has thus been devised in which control influences are transmitted inductively in a manner so that the value or strength of such influence increases with the speed of the train, which is desirable'on account of the shorter period of time through which aninfluence may be trans mitted by such track elements at the higher speeds, and in which the transmission of a control influence at extremely low speeds is accomplished by means responsive to the speed'of the train,and a contact responsive at extremely low speeds and when a vehicle stands still with the influence transmitting elements inregistration, whereby a speed restricting device, whether retarded or immediately effective, and one which continues to be eflective so long as no clearing influence is transmitted from the trackway, may be used to limit the speed of the train.

Having thus shown and described one rather specific embodiment of the invention, it is desired to have it understood that this has been done for illustrative purposes rather than for the purpose of limiting the scope of the invention, and that various changes, modifications and additions may be made to adapt the invention to the particular type of system in connection with which it is to be used. Also it is to be understood that suitable expedients may be used to guard against jars and vibrations both as to the car elements as a whole and the armature 22 associated with the car element L, all without departing from the scope of the present invention or the idea of means underlying the same.

lVhat is desired to be secured by Letters Patent of the United States is 2- 1. In an automatic train control system; the combination of car-carried apparatus comprising, a permissive speed device which normally assumes a certain high permissive speed condition, which it initiated gradually assumes more restricted speed conditions, and which applies the brakes of the train it the actual speed of the vehicle e. ceeds the permissive speed set up by this device, a normally energized electrically operated stick device for maintaining said permissive speed device in its normal condition,

an inductive influence receivlng coil connected in the stick circuit of said stick device adapted to impress a voltage in said circuit when inductively influenced by passing an inductive trackway device and thereby drop said stick device, and other means for dropping said stick device when the speed of the train is reduced below a certain value; and of trackway means for inductively influencing said coil.

2. An automatic train control system comprising, vehicle-carried apparatus including a brake setting device, a permissive speed device normally setting up a certain permissive speed and which if initiated gradually sets up more restrictive speed limits, an actual speed device, means for actuating said brake setting device if the actual speed of the vehicle exceeds the permissive speed set up by this, device, and means partly on the vehicle and partly along the trackway tor automatically initiating said permissive speed device so as to set up lower pern'iissive spccd limits under danger traflic conditions ahead regardless of the speed of the train and including a vehicle-carried tractive armature responsive to flux linking car-carried and traclnvay devices and responsive at extremely low spccds and at zero spec and a coil located in inductive relation with the trackway rcspoir sive at higher speeds.

3. An automatic train control system com prising, vehicle-carried apparatus including a brake setting device, a permissive spccd device normally setting up a ccrtain pcrmissive speed and if initiated gradually setting up more restrictive speed limits, an actual speed device, means for actuatin said brake setting device it the actual spccd of the vc hicle exceeds the permissive speed set up by this device, and means partly on the vehicle and partly along the traclnvay for initiating said permission speed device so as to reduce the permissive speed of the train comprising two distinctive devices one oi which dcpcnds for its operation on magnetic tlux alone and the other of which depends for its opcration on both magnetic flux and movement of the vehicle.

4. An automatic train control system comprising, a permissive speed device changed till luu

ind

ill

(ill

till

nee-side in accordance with the progress of the vehicle along the traclrw'ay when initiated and gradually settingnp lower permissive speed liinits in accordance with such progress, means tor applying the brakes of the usual air brake system of the train actuated it the speed of the vehicle exceeds the permissive speed set up by this permissive speed device, and means partly on the vehicle and partly alongthe traclnvay including a source oi? unidirectional magneto-inctive-iiorce and acting through an intervening air-gap for initiating said permissive speed device ellective at all speeds under danger tral'lic conditions ahead and including a: stationary inert trachway device which does not require any trackivay source of energy.

5 An automatic train control system com prising, a permission speed device changed in accordance with the progress of the vehicle alongthe trackivay when initiated and gradually setting up lower permission speed lim- With such progress, means for ap gilying the brakes of the usual air bralre system ot the rain actuated ii the speed oi? the vehicle cucecds the perniiissive speed set up by this permissive speed device, means partly on the vehicle and partly along lhe traclrivay for initiating said permissive speed device under danger tiniiic conditions ahead ell'cctive by electro-niiagnetic induction at certain speeds and by magnetic induction at other speeds, said last mentioned means including oi ly i u crt traclnvay devices which do not require traclivvay energy,

(3. An automatic train control system coiuprising, a peri'nissive speed device changed in accordance with theprogress oil the vehicle along the track Way when initiated and grad-- ually setting up lower permissive speed limits With such progress, means for applving the brakes oi the usual air bralrc s tern of the train actuated ii the speed oil the vehicle exceeds the permissive speed set up by this permissive speed device, initiating means pa rtly on the vehicle and partly aloiu, the trackvvay and acting; through an interveiling air-gap for initiating said permiio sive speed device and eil'ective at all speeds under danger trailic conditions ahead due to the combined action of magnetic and electro nuigi'ietic induction, said initiating means including an inert tii'ackway device which does not require any ti'nclnvay source o'l cue L and means partly on the vehicle and par v along the trachvvay for restoring said permissive speed device to normal active only uiuilcr clear 'trailic conditions ahead, said rcstoring means including inert traclruav lui'luence coinmuni*atiug appa u'atus requiring no traclrivay energy.

7.. An anton'iatic train control system com- 'irising, a permissive speed device, an actual speed device, a brake setting device, and means for initiating said permissive speed device located partly on the vehicle and partly along the trackivay and including a car-oarried coil adapted to have a voltage in dueed therein to initiate said peruiissi M plied device due to a change pendent on the speed of the vehicle, and other means for initiating; said pia'misvivo speed device responsive to the amount of llux and not the rate oil change of thin and eliec tive if the speed is reduced below a certain value.

8. An automatic train control system ot the iijiterniittent type comprising; lrainrarried ap urratus for restricting the progress of the train; inductive inlluencecommunicating mean partly on the vehicle and partly along the traclr'ivuy for rendering said apparatus ellective; and other means for rendering said apparatus etl'ective, actuated when the speed of the train is less than a certain value 9. In an autonuitic train control system; the conducal-loo ct raucarried iu piavawlus con'iprising, a permissive speed device which when active rllUj JS up a predetermined low perinissive speed limit; a normally energized electrically operated stick device for maintaining said permissive speed. device inactive. means for a pplyi the brakes oil? the train it the actual speed oil the train exceeds the per-- missive speed, an iiuluctivo influence recei v-- ing coil connected in the stic r circuit of said sliclr device adapted to im press a voltage in said circuit when inductively iufluei'iccd by passing an inductive trachivay device and thereby drop said stlclr device, and other n'ieans for dropping said stick device when the speed of the train reduced below a certain value; and ot traclrvvay means tor inductively intluenciiur said coil.

10. An automatic 'ain control systcn'i con1- prising, a permissive speed device, an actual speed device, a brake setting device, and means tor initiation; said permissive speed device located pa on the vehicle and partly along}; the traclrivay and including a car-carried coil adapted to have a voltage induced therein to initiate said permissive speed device due to a, change of magnetic flux dependent on the speed oi. the vehicle, and other means 'lor initialiiinr aid permissive speed device which is responsive to llux ir IGSPGCllVQ ot' the "ate of chance o l such flux.

ill .iin, automatic train control system of the iuterinitteut inductive typo comprising, a brake control device rendered active it the train exceeds a predetcrmincd permissive speed limit, and two sop ate means iuductivel v actuated 'lroni the liraclrivuy tor establii-ihiru such v ec l limit, one oi" said means bciiui; rcspoiuuvo lo the ral'oo'l' l'llitllflfQ ot this and the other bei. r riv-"spousive to llux irrcspective o'l. its rate of change.

123. An automatic train control system of the intermittent inductive type comprising,

of magnetic 'tlui; dc-

ill)

luu

lltl

its rate of change, and separate means also induct vely actuated trom the trackway and effective under favorable tratfic conditions only for discontinuing the imposition of that established speed limit.

13. Influence communicating means for automatic train control systems of the inductive non-physical contact type comprising;

car-carried apparatus including a U-shaped core having a normally energized primary coil, a secondary coil and a movable armature associated therewith; and a train control device controlled by a circuit including a contact operated by said armature and said secondary coil in series.

14. Influence communicating means for automatic train control systems of the inductive non-physical contact type comprising; car-carried apparatus including a U-shaped core having a normally energized primary coil, a secondary coil and a movable armature associated therewith; and a stick electro-responsive train control device having a stick contact associated therewith and normally energized by a circuit including a contact operated by said armature, a source of direct current, said secondary coil and said stick contact in series. I

15. Influence communicating means according to claim 14, having means associated therewith for shunting the contact operated by said armature when the speed of the car is above a certain value.

16. Influence comn'iunicating means for automatic train control systems of the in- 'ductive non-physical contact type comprising; car-carried apparatus including a U- shaped core having a primary coil, a sec ondary coil and a movable armature associated. therewith; a stick electro-responsive train control device having a stick contact associated therewith and normally energized by a circuit including a contact operated by said armature, a source of direct current, said secondary coil and said stick contact in series, and a trackway device for bridging said core upon the passage of a car thereby which trackway device con'iprises an inert core of magnetic material.

17. Influence communicating means for automatic train control systems of the inductive non-physical contact type comprising; car-carried apparatus including a U-shaped core having a primary coil, a secondary coil and a movable armature associated therewith; a stick electro-responsive train control device having a stick contact associated therewith and normally energized by a circuit including a contact operated by said armature, a source of direct current, said secondary coil and said stick contact in series; and a trackway device for bridging said car-carried core upon the passage of the car thereby including a core having a winding thereon which winding is contained in a closed circuit under favorable traflic conditions ahead.

18. Influence communicating means for automatic train control systems of the inductive non-physical contact type comprising; car-carried apparatus including a U-shapcd core having a constantly energized primary coil, a secondary coil and a movable armature associated therewith; a stick electro-responsive train control device having a stick contact associated therewith normally energized by a circuit includin a contact operated by said armature, said secondary coil and said stick contact in series; and a tracky device for bridging said core upon pasge ol the ear-carried core thereby includg" a core having a winding thereon closed in a tie-energized circuit of low resistance under favorable traitic conditions ahead and open-circuited under unfavorable traflic conditions ahead.

19. Influence communicating means for automatic train control systems of the inductive non-physical contact type comprising; car-carried apparatus including a U-shaped core having a constantly energized primary coil, a secondary coil and a movable armature associated therewith; a direct current source of energy for energizing said primary coil; a stick relay; and a circuit including a source of direct current, a front contact of said stick relay, a contact operated by said armature and said secondary coil in series.

20. An automatic train control system comprising, a brake control device; speed control means which it active causes the brake control device to become active and effeet a brake application it a predetermined speed limit is exceeded; and means for rendering said speed control means active comprising; a stick relay normally energized by a circuit including a normally closed contact of said stick relay and an influence receiving coil in which a voltage may be induced by suitable trackway means upon passage of the train by such trackw-rv means so as to eflect de-energization of said stick relay, and supplemental means for dc-encrgizing said stick relay rendered active if the speed of the train is less than a certain value and upon passage of the train by suitable trackway means.

In testimony whereof I atiix my signature.

OSCAR H. DICKE. 

